Effects of dairy intake on weight maintenance.
BACKGROUND
To compare the effects of low versus recommended levels of dairy intake on weight maintenance and body composition subsequent to weight loss.


METHODS
Two site (University of Kansas-KU; University of Tennessee-UT), 9 month, randomized trial. Weight loss was baseline to 3 months, weight maintenance was 4 to 9 months. Participants were maintained randomly assigned to low dairy (< 1 dairy serving/d) or recommended dairy (> 3 servings/d) diets for the maintenance phase. Three hundred thirty eight men and women, age: 40.3 +/- 7.0 years and BMI: 34.5 +/- 3.1, were randomized; Change in weight and body composition (total fat, trunk fat) from 4 to 9 months were the primary outcomes. Blood chemistry, blood pressure, resting metabolism, and respiratory quotient were secondary outcomes. Energy intake, calcium intake, dairy intake, and physical activity were measured as process evaluation.


RESULTS
During weight maintenance, there were no overall significant differences for weight or body composition between the low and recommended dairy groups. A significant site interaction occurred with the low dairy group at KU maintaining weight and body composition and the low dairy group at UT increasing weight and body fat. The recommended dairy group exhibited reductions in plasma 1,25-(OH)2-D while no change was observed in the low dairy group. No other differences were found for blood chemistry, blood pressure or physical activity between low and recommended dairy groups. The recommended dairy group showed significantly greater energy intake and lower respiratory quotient compared to the low dairy group.


CONCLUSIONS
Weight maintenance was similar for low and recommended dairy groups. The recommended dairy group exhibited evidence of greater fat oxidation and was able to consume greater energy without greater weight gain compared to the low dairy group. Recommended levels of dairy products may be used during weight maintenance without contributing to weight gain compared to diets low in dairy products.


BACKGROUND
ClinicalTrials.gov NCT00686426.
Zemel
Michael B
MB
The University of Tennessee, Knoxville, TN, USA. mzemel@utk.edu.
Donnelly
Joseph E
JE
Smith
Bryan K
BK
Sullivan
Debra K
DK
Richards
Joanna
J
Morgan-Hanusa
Danielle
D
Mayo
Matthew S
MS
Sun
Xiaocun
X
Cook-Wiens
Galen
G
Bailey
Bruce W
BW
Van Walleghen
Emily L
EL
Washburn
Richard A
RA